Automatic glue dispensing apparatus



- Oct. 24, 1967 ,J. B. DYESS, JR. ET AL 3,343,519

AUTOMATIC GLUE DISPENSING APPARATUS v Filed June 29, 1964 2 Sheets-Sheet 1 I l 2 1 lj HI Hl WNW;

, INVENTORS JAMES B. DYESSJR. l DANIEL a. TULLIS GEORGE ?2%Rs 5 4 BY mm ATTORNEY Oct. 24, 1967 ss, JR" ET AL 3,348,519

AUTOMATIC GLUE DISPENSING APPARATUS Filed June 29, 1964 2 Sheets-Sheet 2 I NV ENTORS JAMES B DYESS,J'R. DANIEL B. TULLIS ATTORNEY United States Patent 3,348,519 AUTOMATIC GLUE DISPENSING APPARATUS James B. Dyess, .ln, Daniel B. Tullis, and George T. Waters, Conroe, Tern, assignors to Columbian Carbon Company, New York, N.Y., a corporation of Delaware Filed June 29, 1964, Ser. No. 378,712 2 Claims. (Cl. 1182) This invention relates to apparatus for applying glue to object surfaces. More particularly, it relates to a glue dispensing apparatus for automatically dispensing a controlled amount of glue onto a surface of a product container to be unitized.

It is common practice in many industries to package products in containers that are subsequently glued together to provide an integral unit of generally cubical shape, ie a unitized load, for shipping purposes. Generally, a glue having a high shear strength but low tensile strength is employed so that the unitized load can be later disassembled by hand without tearing the containers.

Various mechanical arrangements have heretofore been devised for applying glue to the surfaces of the containers to be unitized. These devices have not proved entirely satisfactory. In some cases, these devices coat the containers with an excessive or insuflicient amount of glue. In other cases, the glue is not applied in a pattern that affords sufficient strength to the unit during shipping without complicating subsequent disassembly. If an excess of glue is applied to the containers, or if the glue is applied in an improper pattern, the containers may tear upon disassembly of the unit, causing spilling of the product in the containers.

It is, therefore, an object of the present invention to provide an improved apparatus for automatically applying glue onto a product container to be unitized.

It is another object of this invention to provide an improved apparatus for automatically applying a controlled amount of glue to a product container to be unitized.

It is another object of this invention to provide an improved apparatus for automatically applying glue in a controlled pattern to the surface of a product container to be unitized.

It is a further object of this invention to provide apparatus for automatically applying glue to a preselected portion of a surface of a product container.

With these and other objects in view, an embodiment of the present invention is hereinafter described with reference to the accompanying drawing. In the drawing, FIGURE 1 is a somewhat diagrammatic representation of an automatically operating apparatus for applying glue to a product container in accordance with the present invention.

FIGURE 2 is a plan view of the apparatus shown in FIGURE 1.

FIGURE 3 is an end view of the apparatus shown in FIGURE 1.

FIGURE 4 is a wiring and fluid flow diagram for the automatically operating glue applying means of the present invention.

With reference to the drawings an endless conveyor belt designated by the numeral 1 is tightly suspended over cylindrical rolls 2 and 3. Each of these rolls has outwardly extending axial shafts 4 that project through pillarblock bearings 5. These bearings are mounted on horizontally extending frame members 6 so as to provide a freely turning conveyor belt assembly supported by vertical legs 7 having affixed thereto support shoes 8 and horizontal stabilizer members 9.

Cylindrical roll 2 has a pulley 10 attached to the extended axial shaft 4. Pulley 10 is rotated by means of belt 1 driven by a gear-headed motor 12 so that belt 1 is moved at an essentially constant rate in the direction indicated by arrow 13.

As ancillary structure, the conveyor belt assembly may be coupled with a roller conveyor 14. Product containers, i.e. substantially rectangular bags or boxes, to be transported onto the conveyor belt 1 may first be placed upon the freely turning rolls 15 and carefully arranged and oriented before being pushed in a direction as indicated by arrow 16 onto conveyor belt 1. Thus, the product containers may be carefully prearranged and caused to move through a predetermined horizontal path over the belt.

For dispensing a controlled amount of glue onto the surface of a product container to be unitized, a glue discharge head assembly 17 is positioned above belt 1. Glue discharge head 17 consists of an automatically operated glue valve 18 and intercommunicating conduits 19 extending laterally in relation to belt 1 and having a plurality of glue discharge orifices 29. Glue discharge head 17 is attached to a horizontal mounting member 21 that is held aloft by a lateral extension 22 of support post 23.

The glue discharge orifices 20 are spaced apart from each other and are in vertical spaced relationship to the container to be glued. Thus, glue is discharged from orifices 20 in a series of parallel streams 24 that flow through a plane essentially perpendicular and transversal to the top surface of belt 1. As a result, bands of glue are deposited on the top surface of a product container transpoited beneath the discharge head.

If desired, support post 23 may be slidably mounted in a socket 25 having a locking screw 26, thereby permitting the spacing between glue discharge head 17 and the surface of the product container being conveyed upon belt 1 to be adjusted. Additionally, horizontal mounting member 21 may be provided with a socket 27 slidable over lateral extension 22 of mounting post 23, permitting lateral positioning of glue head 17 with respect to the product container being conveyed. Socket 27 may be secured in place on the extension 22 by means of a locking screw 28.

Glue is supplied to the discharge head from reservoir tank 29 through line 30. Air or some other suitable gas, may be supplied at a constant, though variable, pressure to the glue reservoir tank through a source line 33, a pressure regulating valve. 34, and feeder line 35 having a pressure indicator 36 installed therein. When tank 29 is not pressurized, it may be filled with glue through funnel 31 and closure valve 32. By establishing a specific pressure within tank 29, a metered stream of glue may be supplied to and released from glue discharge head 17 whenever glue valve 18 is open, glue discharge orifices 20 serving as metering orifices. The rate at which glue flows through glue valve 18 may, therefore, be regulated by a variation of the pressure Within tank 29. Optionally, a flow regulating valve, not shown, may be installed in line 30 to permit or facilitate metering of the stream of glue passing through glue valve 18.

Glue valve 18 is automatically responsive to an externally supplied driving force, i.e., the valve automatically opening in response to the driving force and re- 5 maining closed upon its removal or non-presence. While the glue may be a solenoid valve, a pressure driven glue valve is preferred, e.g., a valve that automatically opens upon supply of a super-atmospheric pressure and is closed during its absence. The pressure driven valve may to advantage be coupled with a pilot valve 37 that permits very rapid development and release of pressure in the glue valve to assure its opening and closing sharply and positively.

Pilot valve 37 may be actuated, i.e., opened and closed, electrically, but alternately it may be actuated by means of fluid pressure. In either case, the pilot valve may be arranged to open automatically upon receipt of an actuating signal. When the pilot valve opens, fluid pressure is passed to the glue valve, which then opens in response thereto, permitting the flow of glue to discharge orifices 20. Glue valve 18 remains open and glue flows through it as long as the actuating signal is passed to the pilot valve. Upon removal or non-presence of the signal, the pilot valve closes. As a result, the glue valve also closes, and the fiow of glue to the conduits 19 is shut off.

As indicated in the drawings, glue valve 18 is a pneumatic valve that opens automatically upon supply of air pressure through pilot valve 37 and line 38. Air is supplied to pilot valve 37 through a source line 33, a pressure regulator 39 and feeder line 40. Pilot valve 37 is an electric solenoid valve that opens upon receipt of an actuating signal current. This valve is held open as long as the current is furnished thereto, and closes and remains closed upon removal and non-presence of the current. As previously indicated, glue valve 18 opens in response to fluid pressure. In the embodiment shown, fluid pressure is supplied to the glue valve only when pilot valve 37 is open.

Actuating signal current is supplied to pilot valve 37 37 through electrical conductors 41 having two serieswired switches 42a and 42b installed therein. These switches are normally kept open by means of spring tension, but may be easily closed by rotation of actuation arms 43a and 4312 through a short arc. Each arm, 43a and 43b, is provided, respectively, with sensors 44a and 44b that determine the presence of a glue-receiving container surface in a selected glue receiving position. These sensors are illustrated as rods that project downwardly to make physical contact with the containers transported by belt 1. Sensors 44a and 44b are urged by the moving product so that actuator arms 43a and 431; are rotated sufliciently to close switches 42a and 42b. Since the switches are wired in series, actuating current is supplied to pilot valve 37 only when both sensors are being urged sufficiently to close their corresponding switches. Both sensors are, therefore, so arranged that the glue valve is opened only when the glue receiving surface of a product container is determined as being present in a selected glue-receiving position.

In the operation of the apparatus of the present invention, a product container to be glued is arranged and properly positioned on roll conveyor 14 so that, when pushed onto belt 1, the product container will contact and urge sensors 44a and 44b while the portion of the container surface that is to be glued is correctly positioned in a selected-glue receiving position. Once the container is on belt 1, it moves at an essentially constant rate of speed, contacting the presence sensors 44a and 44b, thereby causing switches 42a and 42b successively to close. When both switches are closed, pilot valve 37 is actuated, and glue valve 18 opens so that glue is discharged from orifices 20 onto the glue-receiving surface of the product container in a series of bands. As the product container continues to move with the belt, contact between the container and sensor 44a will be discontinued. As a result, switch 42a will open, and the flow of glue through glue valve 18 will be interrupted, even though a portion of the product container surface receiving the glue may remain under glue discharge orifices 20. This is a pre-arranged occurence intended to prevent glue from flowing onto belt 1 or onto an unselected portion of an exposed container surface should glue remaining in conduits 19 continue to discharge from orifices 20 after glue valve 18 has closed. In the absence of such an arrangement, undesired discharge could result from gravity motivated flow occurring after the glue valve has been closed. The duration of a gravity motivated discharge and the length over which a container surface is to be coated with glue are each factors in determining the horizontal spacing needed between sensors 44a and 44b. In some cases, no discharge of glue from the glue head may occur after the glue valve has closed, so that only switch 42b and sensor 44b may be required to effect a satisfactory application of glue to the object surface. However, two sensors and switches may be employed to advantage or in conjunction with different discharge patterns or positions of the glue discharge head to permit coating of only a preselected portion of the glue-receiving surface. For instance, glue head 17 may be located behind sensor 441) instead of the head of it, as shown, thus permitting a portion of the glue-receiving container surface to pass out of the glue discharge region before the glue valve 18 is opened. As previously described, sensor 44a may be so located that the glue valve is closed before the remainder of the surface has passed from the gluedischarge region.

Other means for actuating the glue valve and determining the presence of the glue-receiving container surface may be adapted to the present invention, i.e. electric eyes may be used to detect the presence of a product container in the selected glue-receiving position and for activating the glue valve or a conjunctive pilot valve when the glue valve is driven by fluid pressure. Alternately, electrically or mechanically operated valves may be used instead of switches 42a nd 42b, the valves controlling a fluid pressure supplied to either a pressure activated pilot valve or directly to a pressure responsive glue valve.

For the purpose of illustrating a commercial use of the present invention, the following specific example is presented:

An automatically operated glue applying arrangement as shown in the accompanying drawing was employed for applying glue in controlled amounts in predetermined patterns to substantially rectangular bags filled with carbon black beads. The bags, which had a height of 7", a length of 26" and a width of 18", were placed on a conveying belt moving at the rate of 50 feet per minute and conveyed to the glue-applying region of the apparatus. The glue employed was a water-base, high shear strength, low tensile strength type. A pressure of 8 p.s.i.g. was maintained in the glue reservoir, and air at p.s.i.g. was supplied to the pivot valve. The glue conduits, represented by the numeral 19 in the drawing, were constructed of A" type. Each glue conduit was 6" long and had four 0.0625" diameter glue discharge orifices drilled on 1 centers. The assembled glue head had an 8" lateral span and was spaced 10" above the conveyor belt. The clearance between the bottom of the sensor rods and the top of the conveyor belt was 9 /2", 15 of rotation of the sensor rods being required to close the electrical switches. The horizontal spacing between the sensor rods was 10".

Glue discharged from the orifices in solid, spaced-apart, parallel streams that formed a banded pattern on the top surface of the bags. Even though the bags were conveyed to the gluing operation spaced apart from one another, no glue was discharged onto the conveyor belt,

nor was any problem experienced with over-run of glue onto the sides or ends of the bags.

After gluing, the bags were removed from the end of the conveyor belt and transported by a roller conveyor to a stacking area for forming unitized loads. It was observed that essentially the same amount of glue was applied to each bag and that the pattern of application was within optimum limits. It was further found that the unitized loads were stable during shipment, but were easily disassembled at the receiving point without tearing the bags.

While the invention has been described with respect to particular embodiments, it will be understood that various changes and modifications in the details of the invention herein described and illustrated in order to explain the nature of the invention may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.

Therefore, we claim:

1. A glue dispensing apparatus for applying a controlled amount of glue on to the surface of a container that comprises:

(a) a glue discharge head having a discharge passage terminating in a plurality of discharge orifices, said discharge orifices being disposed in vertical spaced relationship to the container being glued, and being spaced apart from each other, so that glue may be dispensed in a series of parallel streams onto the surface of the container when the container is in a selected glue-receiving position;

(b) conveying means for moving containers to be glued under said discharge orifices;

(c) glue supplying means communicating with said glue discharge head for supplying glue thereto;

(d) a normally-closed, pressure responsive glue control valve communicating with said glue supplying means for controlling the flow of glue to said glue discharge head;

(e) a source of fluid pressure communicating with said normally closed glue control valve;

(f) a normally closed solenoid control valve, said solenoid valve being actuated to open position upon supply of a driving force when a container to be glued is determined as being present in a selected glue-receiving position;

(g) actuating means for the glue control valve responsive to the presence of a container in a selected position comprising:

(1) an electrical circuit adapted to transmit an electrical signal for opening said normally-closed solenoid control valve;

(2) respectively a first and a second normally open electrical switch, each connected in series in said electrical circuit;

(3) respectively a first and a second mechanical actuating means for respectively closing the first and second normally-open electrical switches, said means being responisve to the presence of a container in the selected position;

whereby the presence of a container in the selected position causes the transmission of an electrical signal so as to open the normally-closed solenoid valve, thereby causing fluid pressure to be applied to the normally-closed pressure responsive glue control valve, thereby causing said valve to open so that glue may be discharged through the glue discharge orifices onto the container to be glued.

2. The apparatus of claim 1 and including mechanical means for vertically adjusting the spacing between said glue discharge orifices and the glue-receiving surface of the container to be glued.

References Cited UNITED STATES PATENTS 2,114,723 4/ 1938 Paasche 1182 2,557,479 6/1951 Smith 1182 2,620,767 12/1952 Lehman 1182 2,654,911 10/ 1953 Sharlip et al. 1182 2,701,542 2/1955 Tench 1182 2,804,043 8/1957 Netzley 1182 2,811,130 10/1957 Friderici 1182 2,898,816 8/1959 Keely 1182 X 2,898,820 8/1959 Keely 118--2 X 3,152,923 10/1964 Marshall et a1 118-2 DANIEL BLUM, Primary Examiner. 

1. A GLUE DISPENSING APPARATUS FOR APPLYING A CONTROLLED AMOUNT OF GLUE ON THE SURFACE OF A CONTAINER THAT COMPRISES: (A) A GLUE DISCHARGE HEAD HAVING A DISCHARGE PASSAGE TERMINATING IN A PLURALITY OF DISCHARGE ORIFICES, SAID DISCHARGE ORIFICES BEING DISPOSED IN VERTICAL SPACED RELATIONSHIP TO THE CONTAINERR BEING GLUED, AND BEING SPACED APART FROM EACH OTHER, SO THAT GLUE MAY BE DISPENSED IN A SERIES OF PARALLEL STREAMS ONTO THE SURFACE OF THE CONTAINER WHEN THE CONTAINER IS IN A SELECTED GLUE-RECEIVING POSITION; (B) CONVEYING MEANS FOR MOVING CONTAINERS TO BE GLUED UNDER SAID DISCHARGE ORIFICES; (C) GLUE SUPPLYING MEANS COMMUNICATING WITH SAID GLUE DISCHARGE HEAD FOR SUPPLYING GLUE THERETO; (D) A NORMALLY-CLOSED, PRESSURE RESPONSIVE GLUE CONTROL VALVE COMMUNICATING WITH SAID GLUE SUPPLYING MEANS FOR CONTROLLING THE FLOW OF GLUE TO SAID GLUE DISCHARGE HEAD; (E) A SOURCE OF FLUID PRESSURE COMMUNICATING WITH SAID NORMALLY CLOSED GLUE CONTROL VALVE; (F) A NORMALLY CLOSED SOLENOID CONTROL VALVE, SAID SOLENOID VALVE BEING ACTUATED TO OPEN POSITION UPON SUPPLY FOR A DRIVING FORCE WHEN A CONTAINER TO BE GLUED IS DETERMINED AS BEING PRESENT IN A SELECTED GLUE-RECEIVING POSITION; (G) ACTUATING MEANS FOR THE GLUE CONTROL VALVE RESPONSIVE TO THE PRESENCE OF A CONTAINER IN A SELECTED POSITION COMPRISING: (1) AN ELECTRICAL CIRCUIT ADAPTED TO TRANSMIT AN ELECTRICAL SIGNAL FOR OPENING SAID NORMALLY-CLOSED SOLENOID CONTROL VALVE; (2) RESPECTIVELY A FIRST AND A SECOND NORMALLY OPEN ELECTRICAL SWITCH, EACH CONNECTED IN SERIES IN SAID ELECTRICAL CIRCUIT; (3) RESPECTIVELY A FIRSZT AND A SECOND MECHANICAL ACTUATING MEANS FOR RESPECTIVELY CLOSING THE FIRST AND SECOND NORMALLY-OPEN ELECTRICAL SWITCHES, SAID MEANS BEING RESPONSIVE TO THE PRESENCE OF A CONTAINER IN THE SELECTED POSITION; WHEREBY THE PRESENCE OF A CONTAINER IN THE SELECTED POSITION CAUSES THE TRANSMISSION OF AN ELECTRICAL SIGNAL SO AS TO OPEN THE NORMALLY-CLOSED SOLENOID VALVE, THEREBY CAUSING FLUID PRESSURE TO BE APPLIED TO THE NORMALLY-CLOSED PRESSURE RESPONSIVE GLUE CONTROL VALVE, THEREBY CAUSING SAID VALVE TO OPEN SO THAT GLUE MAY BE DISCHARGED THROUGH THE GLUE DISCHARGE ORIFICES ONTO THE CONTAINER TO BE GLUED. 